This invention generally relates to accessing a host data processor using a terminal connected to the host data processor via a communications network and, more particularly, to an application program at the terminal which allows the user to define the procedure to log on and log off user networks that were undefined at the time the program was written.
Host data processing systems with remote terminals are used in a variety of applications. For example, various information services may be accessed by subscribers with a variety of hardware terminals ranging from so-called "dumb" terminals to personal computers and word processors. The terminals are connected to the host data processing system over commercial telephone lines by first accessing a communication network. The procedure followed by a subscriber in accessing a specific information service is to first dial the desired communication network, then when that connection is made to the information service, the subscriber is prompted at the terminal to enter a user identification number and a password. The host data processing system of the information service responds to the entry of an active user identification number and a corresponding valid password by allowing the subscriber access to the data base.
Another example is a business environment wherein the terminals are either directly cabled to the host or the connection is made by a dedicated telephone line. Specific examples of such systems are electronic funds transfer (EFT) and point of sales (POS) systems. Such systems are "predefined" in terms of the communications network and the protocol for connecting and identifying a terminal to the host. However, the trend for host data processing systems in business environments is to assume a more open architecture in terms of access by a variety of terminals via various communication networks; i.e., an architecture not unlike that described for information services. This would allow, for example, a user to access several different financial institutions at which accounts were maintained by the user with a single terminal for purposes of affecting transactions at those institutions.
The procedure for accessing a host from a remote terminal is termed "logging on". Conversely, the procedure for terminating access is termed "logging off". While logging off is generally less involved than logging on, it is usually necessary to follow some predetermined protocol to effect log off so that the communication network and the host are properly informed that access is to be terminated. The problem in accessing a host data processing system with a remote terminal is that the protocols for log on and log off are not standardized from one system to another. Moreover, the protocols may be subject to change due to assigning new user identification numbers or passwords or as a result of the systems becoming larger and more sophisticated. As a result, the user is confronted with a confusing set of log on and log off protocols.
This problem has been solved in some communication software applications which provide the user with a macro development tool for generating macros for logging onto each of the various host data processing systems that the user may access. However, when using the macro development procedure, the user must use a special macro language and code his or her actual responses and the prompts from the host; i.e., the user must know both the responses and the prompts according to the log on protocol of the particular host for which the macro is being generated.